(1) Field of the Invention
The present invention relates to a network printing system which receives a print request from a terminal through the network and which performs printing in response to the print request. The present invention further relates to a printer and a server (substitute server) used in the network printing system, a method performed by the server for substituting for the printer, and a program making the server execute the method of substituting for the printer. In particular, the present invention relates to a power-saving technology realized by the mentioned system.
(2) Related Art
It has been not only a request of users but also a demand from an environmental viewpoint to reduce consumption power while a printer is in a wait state. Usually, it is a tradeoff between the convenience of users and how much power is to be reduced in a wait state. Specifically, a power reduction at the fixing unit will generate a waiting time for users, and disconnection to a network disables a remote access from the network. In the conventional network environment, it is a usual wait state in which, in the absence of any print request for a predetermined period of time, a power consumption by the fixing unit is reduced, while maintaining a connection to a network.
In the above-mentioned conventional wait state, when a remote terminal requests a printing, the wait state will end automatically, so as to start heating the fixing unit rapidly to reach a temperature required for starting printing. In this wait state, power continues to be consumed by the driver for the LAN interface that is installed inside the printer, such as a PCI card. As a result, there is a limitation for power-saving and it becomes impossible to respond to the need to save enough power.